Rav Yaakov Emden was the beginning of looking at the Zohar in a way that would precede academia.
He decided that some parts were probably authentic documents from ancient sources like ספרא דצניעותא.
Besides that, it is mostly midrashim translated into Aramaic, and has a basic idea that is taking one word to mean the shechina and another word to mean tiferet. It also takes plenty of previous mystics of the Middle Ages [like the Ramban himself] and translates them into Aramaic,
I did not find all that terribly inspiring. I have to add that the mystic tradition never started with the Zohar, but rather with Sefer Yezira, and there were plenty of mystics around in the Middle Ages way before the Zohar. [e.g the Ramban.]
But I would not think to spend time on it because of the phrase עם כל דא a medieval innovation of how to say "although" instead of the regular אף על פי. [How can an invention of the Middle Ages be in a book by R. Shimon ben Yochai? Answer: It is not. The book was written during the Middle Ages. The "Im kol da" is the smoking gun that shows when it was written.
So it is not from R. Shimon Ben Yochai.
[In short, the original events were thus.-- Isaac from Acco was in Spain, and met up with Moshe De'Leon and asked him about the Zohar. Moshe had been selling it page by page claiming it was from an ancient manuscript. So Isaac asked him about this, and said that people were claiming that there is no original. Moshe swore, "May G-d strike me down if I do not have an original manuscript, and I will show you when you come to my home." They had met up in a different city. On the way to his city Moshe de'Leon, in fact, was struck down, but Isaac continued and got to his home where his widow was. He offered to her a large sum of money just to see the original manuscript. She said, "There is no such thing. Rather he (Moshe DeLeon) was writing it from his head."]
